Submission #203241

#	Time	Username	Problem	Language	Result	Execution time	Memory
203241		MKopchev	Triumphal arch (POI13_luk)	C++14	100 / 100	893 ms	26488 KiB

luk

#include<bits/stdc++.h>
using namespace std;
const int nmax=3e5+42;
int n;
vector<int> adj[nmax];

int MX;
int dfs(int node,int parent)
{
    int adj_size=0,more=0;
    for(auto k:adj[node])
        if(k!=parent)
        {
            adj_size++;
            more=more+dfs(k,node);
        }
    int ret=adj_size+more-MX;
    ret=max(ret,0);
    return ret;
}

bool can(int current)
{
    MX=current;
    return dfs(1,0)==0;
}
int main()
{
    scanf("%i",&n);
    int u,v;
    for(int i=1;i<n;i++)
    {
        scanf("%i%i",&u,&v);
        adj[u].push_back(v);
        adj[v].push_back(u);
    }

    int ok=n-1,not_ok=-1;
    while(ok-not_ok>1)
    {
        int av=(ok+not_ok)/2;
        if(can(av))ok=av;
        else not_ok=av;
    }

    printf("%i\n",ok);
    return 0;
}

Compilation message (stderr)

luk.cpp: In function 'int main()':
luk.cpp:29:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%i",&n);
     ~~~~~^~~~~~~~~
luk.cpp:33:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%i%i",&u,&v);
         ~~~~~^~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10